Acquisition of green algal photobionts enables both chlorolichens and chloro-cyanolichens to activate photosynthesis at low humidity without liquid water

Description

This dataset contains meteorological, chlorophyll and LICOR data underpinning the manuscript 'Acquisition of green algal photobionts enables both chlorolichens and chloro-cyanolichens to activate photosynthesis at low humidity without liquid water'. A summary is also provided of the identification of the mycobionts and photobionts for lichen specimens in this study along with the abbreviations with which they are referred to in the other files. Keys to the terms in the dataset are provided on separate pages within each Excel file. All sequence data have been uploaded to GenBank and so are not provided here. Full details of the study and methods are provided in the related manuscript: Worthy F. R.; Schaefer D. A.; Wanasinghe D.; Xu J-C.; Wang L-S.; Wang X-Y. (2024) Acquisition of green algal photobionts enables both chlorolichens and chloro-cyanolichens to activate photosynthesis at low humidity without liquid water. AoB PLANTS In this paper, we tested whether acquisition of novel green algal photobionts could confer photosynthetic advantages which could theoretically expand the ecological amplitude of chloro-cyanolichen relative to cyanolichen. We discovered the presence of multiple novel chloro-cyanolichen associations within clades of the genus Lobaria. Green algal acquisition by supposed cyanolichens had occurred across regions spanning 2000 m to 4000 m elevation. Previous research had demonstrated that whereas cyanobacteria require liquid water for photosynthesis, green algae (and thereby chlorolichen) can photosynthesise with water vapour alone. We show that acquisition of green algal photobionts has allowed chloro-cyanolichen to photosynthesise with water vapour alone. Furthermore, they were photosynthetically active even while desiccated, and at unprecedently low humidity. We propose that in dry habitats this will greatly extend the daily duration spent in a state of net carbon gain. We hypothesise that this would constitute a clear adaptive advantage for chloro-cyanolichen and should enable their colonisation of otherwise unfavourable, dry habitats.

Steps to reproduce

Meteorological data was recorded using UniT loggers (UT330) and Hygrochron iButton loggers (DS1923). In this dataset, records have already been adjusted according to cross-calibration of the different sensors. Chlorophyll content was measured with a microplate spectrophotometer (Infinite M200 Pro KZ10924, Tecan 2013072-333). Chlorophyll content was calculated using Wellburn (1994) equations for DMSO extraction and 1 nm resolution spectrophotometers, with chlorophyll a/b-ratio calculated following Parry et al. (2014). We provide both the raw spectrometry data, a separate dataset for chlorophyll a, b content and a/b, and our R script for calculating chlorophyll content. The R code file also contains explanations of terms used within the data sets, source of calculations and details of the extraction methods. CO2 exchange rates were measured via infra-red gas analysis, using a custom designed circuit attached to a LICOR 830 unit. In this dataset we provide the calculated rates of net photosynthesis, gross photosynthesis and dark respiration for each specimen at each time interval of the experiment. Phylogenetic data has been uploaded to GenBank. However, to facilitate the interpretation of these data sets we include a summary file of the identities of all the lichen mycobionts and photobionts in the study. Detailed descriptions of the full methods underpinning these data sets will be published in the methods section and supporting information of the associated article.

Institutions

Categories

Funding

Licence